New safe method for preparation of sarin-exposed human erythrocytes acetylcholinesterase using non-toxic and stable sarin analogue isopropyl p-nitrophenyl methylphosphonate and its application to evaluation of nerve agent antidotes

Pharm Res. 2006 Dec;23(12):2827-33. doi: 10.1007/s11095-006-9123-1. Epub 2006 Nov 10.

Abstract

Introduction: A non-toxic and stable sarin analogue, isopropyl p-nitrophenyl methylphosphonate (INMP), was synthesized for safe preparation of sarin-exposed acetylcholinesterase (AChE).

Results and discussion: This agent was stable for years, able to be handled in an ordinary laboratory without special care, and its 50% inhibitory concentration (IC50) on 0.04 U/ml human erythrocytes AChE was 15 nM. This reagent was thought to be especially useful since it enables experiments that require sarin-inhibited AChE, such as the development of antidotes for sarin, in a usual laboratory. To demonstrate the usefulness of this method, 40 known and novel pyridinealdoxime methiodide (PAM)-type oxime antidotes were synthesized, and their reactivation activities to INMP-exposed AChE and structure-activities correlation were studied.

Conclusion: Among the antidotes tested in this experiment except for 2-PAM, the compound found to have the highest reactivation activity, was the novel hydrophobic 2-PAM-type compound, 2-[(hydroxyimino)methyl]-1-[4-(tert-butyl)benzyl] pyridinium bromide.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetylcholinesterase / blood*
  • Antidotes / pharmacology*
  • Chemical Warfare Agents / pharmacology*
  • Cholinesterase Inhibitors / blood
  • Cholinesterase Inhibitors / pharmacology*
  • Cholinesterase Reactivators / pharmacology*
  • Drug Evaluation, Preclinical
  • Erythrocytes / drug effects*
  • Erythrocytes / enzymology*
  • Humans
  • Indicators and Reagents
  • Magnetic Resonance Spectroscopy
  • Sarin / analogs & derivatives*
  • Sarin / blood
  • Sarin / pharmacology*
  • Spectrometry, Mass, Electrospray Ionization
  • Structure-Activity Relationship

Substances

  • Antidotes
  • Chemical Warfare Agents
  • Cholinesterase Inhibitors
  • Cholinesterase Reactivators
  • Indicators and Reagents
  • Sarin
  • Acetylcholinesterase